2014, Vol.19, No.3

Journal of The Korea Society of Computer and Information 2023 KCI Impact Factor : 0.65

pISSN : 1598-849X / eISSN : 2383-9945
https://journal.kci.go.kr/jksci

In this paper, we design and implement location information system and user mapping systemusing DSDV(Destination Sequenced Distance Vector) routing algorithm in ad-hoc networkenvironment to efficient manage a number of mobile devices. The software part in proposed systemconstruct ad-hoc network using DSDV routing algorithm and it activate alarm system, such asvibration, when one of devices disappears in the network. The hardware system, called u_LIN(User Location Information Node) construct ad-hoc network and it helps to find a disappeareddevice by using warning system. When we evaluate the performance of our prototype system, wehave checked a correct operation, within the range of 250m in case of 1:1 communication andwithin the range of 100m in case of 1:N communication. The implemented system in this paper ishighly expected to flexibly use in juvenile protection system, stray-child protection system, touristguide system and so on.

In this paper, the two-wheels robot using a predictive controller to maintain the balance of theposture control in real time have been examined. A reaction wheel pendulum control method isadopted to maintain the balance while the bicycle robot is driving. The objective of this researchwas to design and implement a self-balancing algorithm using the dsPIC30F4013 embeddedprocessor. To calculate the attitude in ARS using 2 axis gyro(roll, pitch) and 3 axis accelerometers(x, y, z). In this study, the disturbance of the posture for the asymmetrical propose to overcomethe predictive controller which was a problem in the control of a remote system by introducing the two wheels of the robot controller and the linear prediction of the system controller combines thesimulation was performed. Also, the robust characteristic for realizing the goal of designing a loopfilter too robust controller is designed so that satisfactory stability of the control system to improvestability of the system to minimize degradation of performance was confirmed.

In this paper, we propose a mobile application categorization method using word clusterinformation. Because the mobile application description can be shortly written, the proposedmethod utilizes the word cluster seeds as well as the words in the mobile application description,as categorization features. For the fragmented categories of the mobile applications, the proposedmethod generates the word clusters by applying the frequency of word occurrence per category toK-means clustering algorithm. Since the mobile application description can include someparagraphs unrelated to the categorization, such as installation specifications, the proposedmethod uses some word clusters useful for the categorization. Experiments show that the proposedmethod improves the recall (5.65%) by using the word cluster information.